The present invention relates to a switch for a suspended railway vehicle having elastic noise-suppressing wheels.
Switches for suspended railway vehicles are widely used. Such switches include rails forming three paths one of which branches off into two other paths. The vehicle is provided with rollers arranged on its chassis and supported on the switch during running of the vehicle over the latter. A longitudinal slot is formed between each pair of rails, through which slot the suspension connecting the chassis of the vehicle with its cabin can downwardly extend. When the vehicle runs over the switch from one to another path, one of its wheels enters a gap which is formed between the rails and runs without support. After passing the gap, this wheel engages a portion of one rail of the other path, and the vehicle continues to run along the latter. Since one wheel of the vehicle runs without support, the other wheel is loaded with a doubled operational load. When the vehicle wheels are elastic so as to provide improved noise-suppressing action, the above-mentioned other wheel is correspondingly compressed under the action of the doubled load and thereby the unsupported wheel tends to lower to a level located below the contact surface of the rails. The magnitude of this lowering further increases in the case when the roller device provided on the vehicle for maintaining the same in stable condition on the switch, has significant play.
In order to raise the unsupported wheel lowered in the region of the gap, onto the contact surface of the next rail, a plurality of ramps are provided. Each ramp is arranged on the above-mentioned portions which the unsupported wheel of the vehicle engages after passing the gap. The ramps are arranged on an initial section of the switch or, in other words, on the rails of the branching off path and upstream of the gap, as considered in the direction in which the first path branches off into the second and third paths. The ramps are also arranged on a switch tip or, in other words, on the merging inner rails of the two merging paths and upstream of the gap, as considered in the direction in which the two paths merge into the first-mentioned path. The ramps provided on the switch tip are utilized for running in the branching off direction, either along the stright path or along the branching path. The ramps provided on the initial section of the switch are utilized for running in the opposite direction, that is in the merging direction. All ramps are inclined in the direction of elongation of the rails. Such a construction is disclosed, for instance, in the German patent No. 24 31 867 and the U.S. Pat. No. 3,946,974.
When the double-loaded wheel of the vehicle passes out of the inclined ramp located on the initial section of the switch, only a small section of the contact surface of the respective ramp located laterally of the inclination is available for supporting this wheel. This has the disadvantage that the above-mentioned already significantly loaded wheel is subjected to high contact pressure. As for the ramps which are arranged on the switch tip, there inclination can be also disadvantageous taking into consideration deflection of these ramps during running up of the unloaded wheel of the vehicle thereover, especially when the rails of the switch are not formed as shaped separate members.